GRDH product processing parameters?

Does anyone know the procedures and/or parameters that go into the GRDH products for the 10x10m pixel spacing imagery which have been processed by the S-1 Instrument Processing Facility (IPF)?

I’ve seen the graph ‘Sentinel1SLCtoGRD.xml’ provided in SNAP program, but
the SNAP help says:
‘The Toolbox provides a graph which applies processing to a Sentinel-1 SLC product in order to generate a product similar to a GRD product generated by the IPF. However, the processing applied is not identical.

I’m particularly interested in what speckle filter routines are applied and what process/windowing is used for the up-sampling.

Can anyone help?